awry

When something goes wrong with a decent plan, you say it has gone awry. Losing your backpack is a mistake, but when you realize it contained your ticket and your passport, your vacation plans really go awry.

Wry means "twisted"—so going awry means getting "twisted up." Awry is similar to askew, which means "off, out of line," though when you compare the roots skew "turned at an angle" and wry "twisted" you see the subtle difference between the two words.